EP0940823A4 - Oxide magnetic material, ferrite particles, bonded magnet, sintered magnet, method of manufacturing the same, and magnetic recording medium - Google Patents

Oxide magnetic material, ferrite particles, bonded magnet, sintered magnet, method of manufacturing the same, and magnetic recording medium

Info

Publication number
EP0940823A4
EP0940823A4 EP98943070A EP98943070A EP0940823A4 EP 0940823 A4 EP0940823 A4 EP 0940823A4 EP 98943070 A EP98943070 A EP 98943070A EP 98943070 A EP98943070 A EP 98943070A EP 0940823 A4 EP0940823 A4 EP 0940823A4
Authority
EP
European Patent Office
Prior art keywords
magnet
ferrite
coercive force
recording medium
flux density
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP98943070A
Other languages
German (de)
French (fr)
Other versions
EP0940823A1 (en
EP0940823B1 (en
Inventor
Hitoshi Taguchi
Kiyoyuki Masuzawa
Yoshihiko Minachi
Kazumasa Iida
Miyuki Kawakami
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
TDK Corp
Original Assignee
TDK Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by TDK Corp filed Critical TDK Corp
Publication of EP0940823A1 publication Critical patent/EP0940823A1/en
Publication of EP0940823A4 publication Critical patent/EP0940823A4/en
Application granted granted Critical
Publication of EP0940823B1 publication Critical patent/EP0940823B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/62—Record carriers characterised by the selection of the material
    • G11B5/64—Record carriers characterised by the selection of the material comprising only the magnetic material without bonding agent
    • G11B5/65—Record carriers characterised by the selection of the material comprising only the magnetic material without bonding agent characterised by its composition
    • G11B5/658—Record carriers characterised by the selection of the material comprising only the magnetic material without bonding agent characterised by its composition containing oxygen, e.g. molecular oxygen or magnetic oxide
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
    • C04B35/26—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on ferrites
    • C04B35/2608—Compositions containing one or more ferrites of the group comprising manganese, zinc, nickel, copper or cobalt and one or more ferrites of the group comprising rare earth metals, alkali metals, alkaline earth metals or lead
    • C04B35/2633—Compositions containing one or more ferrites of the group comprising manganese, zinc, nickel, copper or cobalt and one or more ferrites of the group comprising rare earth metals, alkali metals, alkaline earth metals or lead containing barium, strontium or calcium
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
    • C04B35/26—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on ferrites
    • C04B35/2641—Compositions containing one or more ferrites of the group comprising rare earth metals and one or more ferrites of the group comprising alkali metals, alkaline earth metals or lead
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/62—Record carriers characterised by the selection of the material
    • G11B5/68—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent
    • G11B5/70—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer
    • G11B5/706—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer characterised by the composition of the magnetic material
    • G11B5/70626—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer characterised by the composition of the magnetic material containing non-metallic substances
    • G11B5/70642—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer characterised by the composition of the magnetic material containing non-metallic substances iron oxides
    • G11B5/70678—Ferrites
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
    • H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
    • H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
    • H01F1/032—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials
    • H01F1/10—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials non-metallic substances, e.g. ferrites, e.g. [(Ba,Sr)O(Fe2O3)6] ferrites with hexagonal structure
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
    • H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
    • H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
    • H01F1/032—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials
    • H01F1/10—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials non-metallic substances, e.g. ferrites, e.g. [(Ba,Sr)O(Fe2O3)6] ferrites with hexagonal structure
    • H01F1/11—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials non-metallic substances, e.g. ferrites, e.g. [(Ba,Sr)O(Fe2O3)6] ferrites with hexagonal structure in the form of particles
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
    • H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
    • H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
    • H01F1/032—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials
    • H01F1/10—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials non-metallic substances, e.g. ferrites, e.g. [(Ba,Sr)O(Fe2O3)6] ferrites with hexagonal structure
    • H01F1/11—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials non-metallic substances, e.g. ferrites, e.g. [(Ba,Sr)O(Fe2O3)6] ferrites with hexagonal structure in the form of particles
    • H01F1/113—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials non-metallic substances, e.g. ferrites, e.g. [(Ba,Sr)O(Fe2O3)6] ferrites with hexagonal structure in the form of particles in a bonding agent

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Ceramic Engineering (AREA)
  • Power Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Hard Magnetic Materials (AREA)

Abstract

Ferrite particles, a bonded magnet, a sintered magnet and a magnetic recording medium which are obtained from an oxide magnetic material having hexagonal crystalline structure-carrying ferrite as a main phase and containing Ca, R, Fe and M, wherein (M) is one or not less than two kinds of elements selected from Co, Ni and Zn, and (R) comprises at least one kind of element selected from rare earth elements (including Y) and Bi and necessarily includes La, whereby hexagonal ferrite having high saturation magnetization and high magnetic anisotropy, a ferrite magnet having such a high residial magnetic flux density and such a high coercive force that could not be attained in a conventional hexagonal ferrite magnet, and a ferrite magnet having a high residual magnetic flux density, a high coercive force, excellent temperature characteristics of the coercive force and little decrease in the coercive force, especially, in a low temperature region are attained. A ferrite magnet having a high residual magnetic flux density and a high coercive force and produced by using comparatively coarse ferrite particles of a grain size of over 1 νm and a magnetic recording medium having a high residual magnetic flux density and a thermal stability are also attained.
EP98943070A 1997-09-19 1998-09-21 Sintered magnet Expired - Lifetime EP0940823B1 (en)

Applications Claiming Priority (5)

Application Number Priority Date Filing Date Title
JP27392897 1997-09-19
JP27392897 1997-09-19
JP20443398 1998-07-03
JP20443398 1998-07-03
PCT/JP1998/004242 WO1999016086A1 (en) 1997-09-19 1998-09-21 Oxide magnetic material, ferrite particles, bonded magnet, sintered magnet, method of manufacturing the same, and magnetic recording medium

Publications (3)

Publication Number Publication Date
EP0940823A1 EP0940823A1 (en) 1999-09-08
EP0940823A4 true EP0940823A4 (en) 2001-05-23
EP0940823B1 EP0940823B1 (en) 2008-03-05

Family

ID=26514468

Family Applications (1)

Application Number Title Priority Date Filing Date
EP98943070A Expired - Lifetime EP0940823B1 (en) 1997-09-19 1998-09-21 Sintered magnet

Country Status (4)

Country Link
US (1) US6402980B1 (en)
EP (1) EP0940823B1 (en)
DE (1) DE69839208T2 (en)
WO (1) WO1999016086A1 (en)

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WO2000031756A1 (en) 1998-11-26 2000-06-02 Sumitomo Special Metals Co., Ltd. Ferrite magnet powder and magnet using said magnet powder, and method for preparing them
US6908568B2 (en) * 1999-02-15 2005-06-21 Tdk Corporation Preparation of oxide magnetic material and oxide magnetic material
JP3262109B2 (en) * 1999-08-31 2002-03-04 住友特殊金属株式会社 Magnet powder and method for producing the same
JP2002246216A (en) * 2000-12-15 2002-08-30 Sumitomo Special Metals Co Ltd Permanent magnet and its manufacturing method
JP4538991B2 (en) * 2001-02-07 2010-09-08 日立金属株式会社 Permanent magnet and method for manufacturing the same
CN1218330C (en) * 2002-05-31 2005-09-07 三洋电机株式会社 Method for manufacturing oxide magnetic materials and oxide magnetic materials
US7906036B2 (en) 2003-09-12 2011-03-15 Neomax Co., Ltd. Ferrite sintered magnet
US7758767B2 (en) * 2004-09-10 2010-07-20 Neomax Co., Ltd. Oxide magnetic material and sintered magnet
EP1675134A3 (en) * 2004-12-24 2007-01-24 Hengdian Group EMEGC Magnetics Co Ltd Sintered magnet and method for production thereof
US7919007B2 (en) * 2005-12-19 2011-04-05 Tdk Corporation Ferrite magnetic material
EP1968077A4 (en) * 2005-12-28 2009-04-15 Hitachi Metals Ltd Oxide magnetic material
TWI456870B (en) * 2006-03-10 2014-10-11 Hitachi Metals Ltd A method for fabricating a ferrite sintered magnet
JP4508143B2 (en) * 2006-04-06 2010-07-21 株式会社デンソー Fuel pump
JP4685893B2 (en) * 2008-03-31 2011-05-18 Ｔｄｋ株式会社 Manufacturing method of sintered magnet
JP5626211B2 (en) 2009-07-08 2014-11-19 Tdk株式会社 Ferrite magnetic material
BR112012022418A2 (en) 2010-03-10 2024-03-12 Hitachi Metals Ltd SINTERED FERRITE ELECTROMA AND ITS PRODUCTION METHOD
KR101858484B1 (en) 2010-12-28 2018-06-27 히타치 긴조쿠 가부시키가이샤 Sintered ferrite magnet and its production method
SI2881956T1 (en) 2012-07-31 2017-10-30 Hitachi Metals, Ltd. Sintered ferrite magnet and its production method
KR101836964B1 (en) 2012-08-31 2018-03-09 히타치 긴조쿠 가부시키가이샤 Ferrite calcined body, method for producing ferrite sintered magnet, and ferrite sintered magnet
EP2905790B1 (en) 2012-09-28 2024-02-07 Proterial, Ltd. Ferrite sintered magnet and method for producing same
CN105122389B (en) 2013-04-03 2019-09-27 户田工业株式会社 Bonded permanent magnet ferrite powder, bonded permanent magnet resin combination and the formed body using them
KR20150010519A (en) 2013-07-19 2015-01-28 삼성전자주식회사 Soft magnetic exchange coupled composite structure, high frequency device components comprising the same, antenna module comprising the same, and magnetoresistive device comprising the same
WO2015025589A1 (en) * 2013-08-22 2015-02-26 株式会社村田製作所 Oxide ceramic material and ceramic electronic component
WO2015050119A1 (en) 2013-10-02 2015-04-09 戸田工業株式会社 Ferrite particle powder for bonded magnet, resin composition for bonded magnet, and molded article using ferrite particle powder and resin composition
RU2542065C1 (en) * 2014-02-11 2015-02-20 Федеральное государственное бюджетное учреждение науки институт физики им. Л.В. Киренского Сибирского отделения Российской академии наук Lutetium-containing spin-glass magnetic material
WO2015178080A1 (en) * 2014-05-21 2015-11-26 株式会社村田製作所 Oxide ceramic and ceramic electronic component
WO2016052483A1 (en) * 2014-10-01 2016-04-07 戸田工業株式会社 Ferrite particle powder for bonded magnets, resin composition for bonded magnets, and molded article using same
DE102017200810B4 (en) * 2016-01-26 2021-03-18 Würth Elektronik eiSos Gmbh & Co. KG Component for electromagnetic interference suppression and method for producing a component for electromagnetic interference suppression
US11450458B2 (en) 2018-02-26 2022-09-20 Tdk Corporation Ferrite sintered magnet, motor and generator
CN108774005B (en) * 2018-05-24 2021-08-24 成都锦钛精工科技有限公司 Vitreous additive, preparation method and application in preparation of ferrite permanent magnet material
CN109192434B (en) * 2018-09-21 2020-08-21 江门杰富意磁性材有限公司 Preparation method of soft magnetic ferrite material
CN113677625A (en) * 2019-03-29 2021-11-19 Tdk株式会社 Ferrite sintered magnet, ferrite particles, bonded magnet, and rotary electric device
CN112645704B (en) * 2020-12-28 2023-02-03 安徽龙磁科技股份有限公司 Preparation method of high-performance ferrite
JP2022151625A (en) * 2021-03-24 2022-10-07 Tdk株式会社 Ferrite sintered magnet, ferrite particle, bonded magnet, and rotating electrical machine
CN116120049B (en) * 2023-02-17 2024-01-19 矿冶科技集团有限公司 Preparation method of calcium lanthanum cobalt ferrite magnet, calcium lanthanum cobalt ferrite magnet and application

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Also Published As

Publication number Publication date
DE69839208T2 (en) 2009-03-12
DE69839208D1 (en) 2008-04-17
US6402980B1 (en) 2002-06-11
WO1999016086A1 (en) 1999-04-01
EP0940823A1 (en) 1999-09-08
EP0940823B1 (en) 2008-03-05

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